📖 Notes
LESSON 09 OF 17
Functional Groups & Reactions
Functional Groups & Reactions
Every major functional group MDCAT expects you to recognise, plus the core reaction types — substitution, addition, oxidation, and esterification.
Functional Groups
Key Functional Groups
Functional Group Reference
REFERENCEAlkane: -CH3 (C-C single bonds) Alkene: C=C double bond Alkyne: C≡C triple bond Alcohol: -OH Aldehyde: -CHO (terminal) Ketone: C=O (not terminal) Carboxylic acid: -COOH Ester: -COO- Amine: -NH2 Amide: -CONH2
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Alcohols
Ethanol in hand sanitiser and beverages
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Esters
Give fruits and perfumes their smell
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Carboxylic Acids
Acetic acid is the acid in vinegar
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Amines
The -NH₂ group found in every amino acid
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Alkanes
Candle wax and LPG/petrol are alkane mixtures
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Alkenes
Ethylene is the raw material for plastics (polyethylene)
Core Reaction Types
- Alkanes + halogens → substitution (requires UV light)
- Alkenes → addition reactions
- Esterification: RCOOH + ROH ⇌ RCOOR + H₂O
Alcohol Oxidation Ladder
- 1° alcohol → aldehyde → carboxylic acid
- 2° alcohol → ketone
- 3° alcohol → no oxidation possible
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Exam tip
MDCAT often gives you a structure and asks which functional group is present, or gives a reactant and asks what reaction type follows. Recognising the group from its drawn structure is worth more practice time than memorising names alone.